Apparatus for manufacturing ceramic coil forms



Nov. 21, 1944. w. M. SIESEL 63,

APPARATUS FOR MANUFACTURING CERAMIQ COIL FORMS v Filed April 27, 1945 6 Sheets-Sheet 1 Nov. 21, 1944. w. M. SIESEL 2,363,443

APPARATUS FOR MANUFACTURING CERAMIC CQIL FORMS Filed April 27, 1945 e Sheets-Sheet 2 AWW Nov. 21, 1944. w M SIESEL 2,363,448

APPARATUS FOR MANUFACTURING CERAMIC COIL FORMS Filed April 27, 1945 6 Sheets-Sheet 5 Nov. 21, 1944. slEsEL 2,363,448

APPARATUS FOR MANUFACTURING CERAMIC COIL FORMS Filed April 27, 1943 6 Sheets-Sheet 4 Nov. 21, 1944. w. M. SIESEL APPARATUS FOR MANUFACTURING CERAMIC COIL FORMS 6 Sheets-Sheet- 5 Filed April 27, 1945 Nov/21, 1944. I w. M. SIESEL APPARATUS FOR MANUFACTURING CERAMIC COIL FORMS Filed April 27., 1945 6 Sheets-Sheet 6 Patented Nov. 21,;1944

UNITED, STATE APPARATUS FoR MANUFACTURING CERAMIG con FoRMs William M. Siesel, Mrrisville,Pa.

Application April 27, 1943, Serial No. 484,792 i 20 Claims. ,(01. 51-103) This invention relates-to centerless abrading or cutting apparatus and particularly to apparatus for the manufacture of ceramic coil or other basically cylindrical, forms. More particularly the invention relates toapparatus foruse in'manufacturing small 0011 forms and insulators of the type which have come into common use in radio signalingapparatuses, Although the invention will be hereinafter described, for purposes of illustration, in its application to the manufacture of ceramic coil forms, it will be understood that many features of the invention are widely applicable in the centerless grinding art.

Such coil forms must be very accurately constructed and free from defects, in many instances a slight chipping of the corners of the ends of the coil being cause for rejection. Due tothe nature of the material, profiling and other forming operations on the blank from which the coil form is finally produced must necessarily be done prior to firing of the form. The material is accordingly in an extremely brittle and fragile state with the result that ordinary cutting operations performed thereon will tend to cause defects in the completed blank. Such defects are particularly noticeable .at the e'nds o'f the blank where ordinary cutting operations willchip the corners of the cylinder rendering a large partof the product unusable.

' readily adjusted to accommodate a number of difiering sizes of the forms and which will be, to the greatest possible extent, automatic in its operation.

Another object of the invention is the provision of an arrangement such that the work is firmly held in positionv for engagement by the cutting implements and is at the sametime free to rotate during. the cutting operation.

These andother objects I attain by the constructions shown inthe accompanying drawings, wherein for the purpose ofillustration, I have shown preferred embodiments of my invention and wherein: 1

Figure 1 is a front elevation of a cutting and profiling'machineythe connections of the drive motor being illustrated in the accompanying Figure 1a;

Figure 2 is an end elevation of the machine;

Figure 3 ,is a section on line 3-3 of Figure 2 Figure 4 is a transverse sectional view through the machine, the parts beingflillustrated in the position which they assume when the blank is in engagement with the cuttin discs;

Figure 5 is a view similar to that of Figure '4, but with the parts disposed at the opposite extreme of their relative movement and illustrating the discharge of the complete form from the machine;

Figure 6 is a fragmentary sectional view showing the cradle at a position intermediate to those Figure 10 is a section similar to that of Figure 9 i and showing the cradle at the opposite extreme of its motion; I v

Figure 11 isa fragmentary front elevation of thestructure illustrated in Figures 9 and 10;

Figure 12 is a section on line l2 I2 of Figure 10;

Figure 13 is a perspective view of the holddown employed in the construction of Figures 9 to12; and a I Figure 14 is a side elevation of a plurality of coil forms which have been formed by the structure of Figures 9 to 13, from a blank, the original form of which is generally designated by con-'- struction lines.

' Referring now to the drawings and more particularly to Figures 1 to 6 thereof, the numeral l0 designates a suitable frame having at one end thereof bearings ll mounting an abrading wheel shaft l2, the shaft being driven at a relatively high speed by any suitable means such as motor I3, As herein show the shaft [2 mounts a plurality of cut-off .discs I4 and profiling discs I5, the position and size of which is determined by the particular coil'form Hi to be formed and being suchas to cut the blank B from which this form is produced. to the proper and exact length and to form profile grooves l1 therein.

Supported by bearings l8 and I9 arranged adjacent the opposite end of the frame ill is a shaft 20, hereinafter to be referred to as the cradle shaft. This shaft parallels shaft 12 and projects adjacent thereto in opposition to the discs l4 and I 5 carried thereby. The disc confronting portion of shaft 20 is provided with spaced pairs of bearing arms 2|. mount a pair of parallel blank supporting shafts 22, which preferably are provided with collars 23 arranged to clear the discs l4 and I5 and to support the blank B between the cutting discs l4. Arranged beneath the frame I is a shaft 24 like- Wise driven by motor I3. This shaft, as by a sprocket and chain drive indicated at 25, drives a rotatable collar 26 mounted upon the cradle shaft 20 and including a spur gear 21. Shafts 22 have pinions 28 meshing with spur gear 21 with the result that these shafts are driven in the same direction for a purpose presently to appear.

Shaft 24 through a counter shaft 29, introduced to permit feeding speed regulation, drives a unit 30 comprising a cam'3l. This cam engages a roller 32 upon pivoted arm 33 to which is attached a sprocket chain 34 trained over a sprocket 35 secured to cradle shaft 20. The opposite end of this sprocket chain i connected by a spring 36 to the frame ID in order that proper contact between the arm 33 and cam 3| may be maintained. Each rotation of the cam 3| causes the cradle shaft to oscillate, moving the cradle formed by shafts 22 from the position illustrated in Figure 4 to the position illustrated in Figure and back again. As the cradle moves from the position of Figure 4 to that of Figure 5 a completed form 16 is discharged and the operator places a new blank in the position indicated by the dotted lines Bl of Figure 5. The succeeding movement of the cradle shifts this form into engagement with the cutting and profiling discs l4 and I5 as indicated by the dotted line position B2 of that figure.

While the groove provided by spacing of the shafts forming the cradle together with the pressure exerted during the cutting operation will serve to hold the blank in position for the operations where these operations are of a light nature, with heavier operations it becomes necessary to provide a means for insuring proper positiomng of the blank. One form of this mechanism is illustrated in the figures now under discussion and comprises a retaining belt 31. In order that this belt may hold the work-piece in proper position during the cutting operation and provide slack to permit ready insertion of the substitute blank, I mount at the front of frame In bearings 38 and 39 in which is rotatably mounted a shaft 40 driven from a second sprocket 4i forming a portion of the rotatable collar unit 22. This shaft mounts a driving pulley 42 for belt 37, the belt being trained over this pulley, beneath an idler pulley 43 and between this pulley and an elevated pin 44, thence over the rearmost of shafts 22 and about a stationary idler 45 to the drive pulley 42. The speed of rotation of the drive pulley 42 is preferably such that the linear speed of the belt 31 is the same as the peripheral speed of the blank supporting collars 23.

Disposed between bearing 39 and shaft 40 is a sleeve 46 having secured thereto a collar 41 com prising an arm 48 bearing at its outer end idler 43 and pin 44. The opposite end of this sleeve has secured thereto a rocker 49 which is connected by a torsion spring 50 to the adjacent end of bearing 39. Secured to the cradle shaft These bearing arms rotatably 20 is an arm 5|, having attached thereto a link 52 connected to the rocker arm 49 on sleeve 46. The connection provided is a lost motion con nection which, when shaft 29 is in a position illustrated in Figure 5, is in its full take-up position and has by its engagement with arm 49 oscillated sleeve 46 in bearing 39 and elevated arm 48 thereby retracting idler pulley 43 and elevating the upper end of belt 31 through pin 44. This permits the completed article to be discharged from the cradle to trough 54 and the replacement of the completed article with a blank B. As the cradle moves to the position of Figure 4, sleeve 46 is rotated under the influence of torsion spring 50 to move the arm 48 to bring idler pulley 43 into tensioning engagement with the belt as indicated in that figure. In the modified construction in Figure 7 a standard 55 is secured to a suitable support, preferably the dusthood 56. A holding finger 57 is pivoted to the support 55 as at 58 and is spring urged for engagement with the blank as by means of spring 59.

In Figures 9 to 14 inclusive, I have illustrated an apparatus particularly adapted for the handling of'very small tubes or cylindrical pieces of this character. In the smaller sizes, it becomes highly desirable that the support for the workpiece be made as unitary as possible and that the construction be such as to readily adapt itself to the simultaneous formation of a plurality of the forms. To this end the supporting collars utilized upon the cradle shafts 22 are relatively closely spaced, the spacing being just sufficient to admit passage between the adjacent collars of the shaft more nearly adjacent to the discs of the peripheral portions of the cutting and grinding disc [4 and IS. The peripheral portions of the other of the shafts interdigitate with those of the shaft just mentioned so that a substantially continuous support is provided for the blank MB utilized in the machine, thus eliminating probability of breakage through flexing of the relatively fragile tube.

In a construction of this character, the peripheries of the cutting discs and contouring discs must extend between adjacent portions of the supports and, in many cases, the discs themselves will be relatively closely spaced. In order to. provide a means for holding the relatively small article in position, I provide a pair of arms 60 upon the cradle shaft 20,- these arms supporting by oscillation a frame 6| to which is secured a plurality of fieXible fingers 62 arranged to extend between adjacent discs of the cuttingand contouring shaft and to likewise clear the supporting collar portions of shafts 22. A spring 93 normally positions these fingers for engagement with the supported blank and the fingers themselves are preferably so formed as to provide shoulders 54 which will prevent movement of the work-piece under the influence ofthe relatively large collar portions of shafts 22 to a position where the work-piece would be improperly acted upon by the discs.

In order that the completed forms may be readily removed, I secure to the oscillatory frame 6| an arm 65 having .a roller 66 which, a the cradle is moved to its idle position, comes into engagement with a cam 5! carried by the frame It] and is thereby shifted against the action of spring 63 to elevate the spring fingers 62. It will be noted from Figure 10 that at the time when the cradle is in its idle position the upper surfaces of the collars of the outwardly disposed aecacas shaft are substantially horizontal and since their direction of rotation isythat'indicate'dby, the ar-I- row on this figure, the collars will themselves tend to shift the completed forms and discharge them tothetro-ugh 54. 1-.- I

In either of the forms of the inventiondescribed, it is readily possible to vary the effective size of the cradle through 'certain limits the bearing supports of shafts 22being, secured to the .cradleshaft 20 through clamping collars 6.8,. It will also obviouslybe possible to make' various other changes andadjustmentsin ,the' rnechanism enabling its ready adaptation to forms other than those particularly illustrated. I do not, accordingly, wish to be understood as limiting myself to the present structures except as hereinafter claimed.

I claim:

1. A machine of the class described comprising a driven shaft bearingan abrading wheel, a blank supporting cradle oscillatable. about, an axis paralleling the axis of the shaft andineluding parallel blank supports rotatable about axes paralleling the axis of the shaft, means to oscillate the cradle to shift a blank on said blank supports into and out of engagement with said abrading wheel, and means to rotate said blank supports in a direction such and at a rate such that the adjacent peripheral portions of the abrading wheel and blank are moving in the same direction at different speeds.

2. A machine according to claim 1 having therein means to secure said supports in.Vari-' 'ous desired spaced relations.

3. A machine according to claim 1 having therein. means yieldably maintaining the blank in position on said supports.

4. A device as claimed in claim 1 having therein a device for yieldably maintaining the blank in position on said supports comprising a belt.

and means to drive said belt at the same linear speed as the peripheries of the blank supports.

7. A device as claimed in claim 1 having therein a device for yieldably maintaining the blank in position on said supports comprising a belt,

means for'alternately .tensioning said belt and for loosening the belt and moving it out of operative engagement with the blank, and means to drive said belt at the same linear speed as the peripheries of the blank supports.

8. A device as claimed in claim 1 having therein means for maintaining the blank in position on said supports comprising a spring finger.

9. A device as claimed in claim 1 having thereshifted to move the blank out of engagement with saidrabrading wheel, including a support for said spring finger mounted. for movement about a'pivot fixed with relation to the cradle, and cam means operated by shifting of the spring finger support for oscillating said support about the pivot; thereof. I 1

- 11.1A' cut-off and cut-'ofi machine accordin to claim 1 having therein retaining means' for holding. the blank'in position on the supports, and means to move said retaining means intoand out of engagement with the blank as said i-blank is moved into and out of engagement with said abrading wheel. YT a l ,,-12 A'device as claimed in claiml having therein a device for yieldably maintaining the blank in position on said supports comprising a belt, and means operating in timed relation to the oscillation of the cradle for alternately tensioning said belt and for loosening the belt and moving it out of operative engagement with the blank.

13. A device as claimed in claim 1 having therein a device for yieldably maintaining the blank in position on said supports comprising a belt, means operating in timed relation to the oscillation of the cradle for alternately tensioning said belt and for loosening the belt and moving it out of operative engagement with the blank, and means to drive said belt at the same linear speed as the peripheries of the blank supports.

14. A machine according to claim 1 in which the driven shaft bears a plurality of laterally spaced cutting and profiling discs, and in which the parallel blank supports each comprises a shaft rotatable about an axis paralleling the axis of the shaft and a plurality of supporting discs secured to said shaft, and in which the supporting discs of said shafts are staggered with relation to one another and with relation to the cutting discs whereby the discs of each shaft blank supporting discs secured to said shaft,

means to oscillate the cradle to shift a blank on said blank supports into and out of engagement with said abrading wheel, means to rotate said 16. A device as claimed in claim 15 having therein means for maintaining the blank in position on said supports comprises a spring finger.

17. A device as claimed in claim 15 having therein means for maintaining the blank in position on said supports comprises a spring finger and means to automatically move said finger out of engagement with the blank as the cradle is shifted to move the blank out of engagement with said abrading wheel.

18. A device as claimed in claim 15 having therein means for maintaining the blank in position on said supports comprises a spring finger, means to automatically move said finger out of engagement with the blank as the cradle is shifted to move the blank out of engagement with said abrading wheel, comprising a support for said spring finger mounted for movement about a pivot fixed with relation to the cradle, and cam means operated by shifting of the spring finger support for oscillating said support about the pivot thereof.

19. A machine for profiling blanks, comprising a rotating shaft bearing abrading wheel, a blank supporting cradle oscillatable about an axis extending alongside and in the same gen- WILLIAM M. SIESEL. 

